DISSERTATION RESEARCH: Evaluating likelihood-based fossil-calibraition methods and timing of repeated incercontinental dispersal in a fossil-rich clade of Boraginaceae

论文研究：评估基于可能性的化石校准方法以及在富含化石的紫草科进化枝中反复大陆扩散的时间

• 批准号: 1210833
• 负责人: Bruce Baldwin
• 金额: $ 1.49万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2014-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1210833&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Evaluating; likelihood; based

Fossils are routinely used as the most defensible method for calibrating phylogenetic hypotheses to absolute time. Calibration is often required before ideas can be tested, such as timing of a prehistoric event or rate of change of a trait. This project examines a fossil rich plant group, the Cryptanthinae (Boraginaceae), to test two recently proposed but untested methods for incorporating fossils in phylogenetic analyses. After evaluating these methods, the resulting time-calibrated hypothesis of phylogenetic relationships will be used to examine the New World amphitropical disjunction, a distribution pattern seen in the Cryptanthinae and many other groups of plants that is likely the result of long-distance dispersal by birds between North and South America. This project will result in three main contributions to science. First, evaluation of novel methods for incorporating fossil data into phylogenetic studies will benefit all future studies using fossil data. Importantly, these methods can be generalized to any study using morphological data. Second, New World amphitropical disjunction is common yet understudied. This study will test current hypotheses regarding this biogeographic pattern. Finally, this project will generate a hypothesis of relationships in the Cryptanthinae that will inform taxonomy and conservation in this large and ecologically important plant group.

化石通常被用作将系统发生假设校准到绝对时间的最可靠的方法。在测试想法之前通常需要进行校准，例如史前事件的时间或特征的变化率。该项目研究了富含化石的植物群 Cryptanthinae（紫草科），以测试两种最近提出但未经测试的将化石纳入系统发育分析的方法。在评估这些方法之后，由此产生的系统发育关系的时间校准假设将用于检查新大陆两性分离，这是在隐花亚科和许多其他植物类群中看到的一种分布模式，很可能是鸟类长距离传播的结果北美和南美之间。 该项目将为科学做出三项主要贡献。首先，评估将化石数据纳入系统发育研究的新方法将有利于所有未来使用化石数据的研究。重要的是，这些方法可以推广到任何使用形态学数据的研究。其次，新大陆两性分离现象很常见，但尚未得到充分研究。这项研究将测试有关这种生物地理模式的当前假设。最后，该项目将产生隐花亚科的关系假设，为这一大型且具有重要生态意义的植物群的分类和保护提供信息。